A DUAL BAND SLOT ANTENNA FOR WIRELESS APPLICATIONS WITH CIRCULAR POLARIZATION

In recently developed wireless communication systems, circular polarization (CP) antennas are used for communication links to reduce the natural loss effect in receivers. Therefore, in this paper, a dual-band microstrip slot antenna based on a parallel split ring resonator with circular and linear polarization which can be used for wireless and WiMAX applications is presented. The final antenna to design is based on inspired split ring resonators (SRR) to achieve circular polarization and compact size and with special parallel form of the SRR and straight feed line. We have achieved higher bandwidth in the requested frequency range with dual-band characteristics. The final antenna has a bi-directional pattern with circular polarization at the range of 2.9–3.65 GHz and bandwidths of 2–3.6 and 3.8–4.8 GHz with VSWR < 2 for WLAN, Bluetooth and radar applications for IEEE WLAN protocol with gain of 5– 6 dBi, respectively. The size of the prototype patch antenna is 40×40 mm2. It is designed and fabricated on an FR-4 low cost substrate with εr = 4.4 and a thickness of 1.6 mm. It is simulated using HFSS full wave software. In addition, the experimental results are presented and compared with simulation for VSWR, radiation patterns and axial ratio. The periodic analysis has been used for extracting the metamaterial parameters.